This invention relates in general to an improved supraglottic device for airway management. In particular, this invention relates to an improved structure for such a supraglottic device that is easier to insert into a patient and is more readily tolerated by a conscious or unconscious patient when in inserted in the patient's mouth and airway.
Airway management generally includes a set of maneuvers and medical procedures performed to prevent and relieve airway obstruction. This ensures an open pathway for air exchange between a patient's lungs and the atmosphere. This may be accomplished by either clearing a previously obstructed airway, or by preventing airway obstruction in cases such as anaphylaxis, an obtunded patient, or medical sedation. Airway obstruction can be caused by the tongue, foreign objects, the tissues of the airway itself, and bodily fluids such as blood and gastric contents, i.e., aspiration.
Airway management is commonly divided into two categories: basic and advanced. Basic techniques are generally non-invasive and do not require specialized medical equipment or advanced training. These include head and neck maneuvers to optimize ventilation, abdominal thrusts, and back blows.
Advanced airway management techniques require specialized medical training and equipment, and may be further categorized anatomically into supraglottic devices, such as oropharyngeal and nasopharyngeal airways, infraglottic techniques, such as tracheal intubation, and surgical methods, such as cricothyrotomy, and tracheotomy.
Artificial airways include endotracheal tubes, laryngeal mask airways, and oral airways. Known endotracheal tubes are configured to pass through the nose or mouth between the vocal cords and into the trachea. This placement is beneficial in patients suffering from respiratory insufficiency and coma as well as many patients under general anesthesia. A laryngeal mask airway is configured to pass through the mouth and cover and surround the larynx during general anesthesia, but typically is not tolerated by a patient while awake.
Typical oral airways are configured to pass over and past the tongue in the midline to hold the tongue forward. Oral airways may be placed in cardiac arrest patients to temporarily open the airway if it is obstructed prior to the placement of an endotracheal tube. Anesthesia providers often place an oral airway in heavily sedated patients to keep the airway open, or in patients who are recuperating from anesthesia in recovery room, but become more sedated after narcotics are given to control post operative pain, and thus may lose their airway.
One known oral airway is an oropharyngeal airway, also known as a Guedel pattern airway that is used to maintain or open a patient's airway. The oropharyngeal airway does this by preventing the tongue from covering the epiglottis, which could prevent the person from breathing. When a person becomes unconscious, the muscles in their jaw may relax and allow the tongue to obstruct the airway.
Artificial airways are instrumental in maintaining open airways in many groups of patients including surgical patients, comatose patients, and patients with sleep apnea. Any loss of an open airway may result in low oxygen levels and high carbon dioxide levels which may lead to cardiovascular compromise, myocardial infarction, brain damage, and death. The loss of an airway for as little as a few minutes, even in a healthy person, may rapidly lead to irreversible brain damage or death.
Sleep apnea is becoming a wide spread health problem affecting nearly 25% of the adult population, and which may lead to inability to concentrate, hypertension, daytime somnolence, type 2 diabetes, increased incidence of accidents at work and by automobile, and in the worst case, stroke and cardiac failure.
The industry standard oral airways are very poorly tolerated in an awake patient because of the shape and location of a properly placed airway, and because of the negative reaction of the oral and pharyngeal structures to any pressure or stimulation. A typical oral airway may therefore lead to coughing, retching, vomiting, and excessive salivation, and can lead to bronchospasm, which is similar to an asthma attack, and laryngospasm, which is an involuntary closure of the vocal cords that may lead rapidly to cardiac arrest in children.
Disadvantageously, placement of the oral airway may also push the base of the tongue over the airway closing it off, and worsening the airway obstruction.
During sedation anesthesia, also called twilight sleep, even with continuous infusions of sedatives, the depth of sedation and the stimulation of surgery varies. With a current industry standard oral airway in place, an increase in surgical stimulation or a decrease in sedation level and movement of the airway near the epiglottis may lead to sudden explosive coughing, breath holding, valsalva, i.e., bearing down which may increase blood pressure and venous pressure and which may cause bleeding into the tissues, struggles to secure the airway, risks to maintaining the sterile surgical field, and delays in completing surgery.
Thus, it would be desirable to provide an improved structure for a supraglottic device that is easier to insert into a patient and is more readily tolerated by a conscious or unconscious patient when in inserted in the patient's mouth and airway.